Portable or ambulatory drug administration devices such as infusion pumps are commonly used to deliver liquid medicaments over an extended time period. Those infusion pumps are, among others, used in the therapy of diabetes mellitus by CSII (Continuous Subcutaneous Insulin Infusion). In the following, reference is made to these types of devices without limiting the scope of the invention to this particular application.
Typical insulin pumps can deliver insulin in a substantially continuous way according to a patient-specific basal administration profile which is variable over the time of day. In addition, those pumps can administer drug boli on demand, for example to compensate for carbohydrate intake and/or undesirably raised blood glucose levels. Those drug boli may be administered according to a pulse profile in a short time of typically less than one minute or may be administered according to one or multiple bolus administration profiles over an extended time period, of, e.g., 30 min or one hour. Drug administration according to the basal administration profile and one or multiple bolus administration profiles is superimposed. Some devices allow the user to temporarily modify the administration in order to meet the special requirements which are present, among others, during illnesses or sportive activities.
Known ambulatory infusion pumps can typically be operated in two to three different main operation modes, a run mode, a stop mode in which substantially no drug is administered and sometimes also a suspend mode which is provided for temporarily suspending the drug administration.
Furthermore, the administration device may have one or multiple error modes to which the device is switched upon the occurrence of an error condition, such as a technical device error, or a blockage of the infusion cannula. In prior art devices, those error modes can be considered as stop modes, too.
In each mode only certain commands/orders may be executed and certain actions may be performed, respectively. In the run mode drug is administered as described above. Exchange of a drug cartridge such as an insulin cartridge or exchange of infusion line may only be performed when the operation mode is the stop mode.
Nowadays, whenever the stop mode is activated upon occurrence of an error condition or resulting from a dedicated user action stopping the drug administration, administration of any bolus according to a bolus administration profile as well as any temporary modification of the administration are cancelled. The administration can be resumed only according to a default administration profile when switching from the stop mode back to the run mode. The stop mode may require a dedicated user action/user input for returning to the run mode. The default administration profile is given by the basal administration profile without any temporary modifications.
U.S. Pat. No. 7,204,823 B2 discloses an infusion pump having a suspend function for temporarily suspending medication administration by the infusion pump. The suspend mode has to be specifically selected and activated by the user. When the user resumes administration, he may select which of those administration profiles which where active when suspending administration are to be resumed.
User faults and inappropriate infusion may occur when an administration device is switched from a stop mode to the run mode. In such cases, the user has to memorize and to manually reactivate or reprogram all bolus administration profiles and temporary modifications to the administration which where active when changing into the stop mode. This step is likely to be forgotten in particular if the stop mode has not been selected intentionally by the user but has been activated because of an error condition.